Sprites
Sprites are the images that can be used in the various layers of gridslots on the map. To make browsing easier, sprites are split up over various categories.
The FTSA editor can handle up to 64 sets of sprites, each of these sets can have up to 64 styles and in each style there can be up to 64 images. In the editor, images are named such to make it easy to see what set and style the image belongs to. The name format is setname_stylename_spriteXX, where XX is 00 to 63.
Not all of the images that the editor has access to, may be supported by the target game for which the editor is being used. Each compatibility mode therefor has a list of sets and styles it supports as well as the number of sprites for each of those set & style combos. The available sprites for a single set-style combo always starts with the first sprite, sprite00, so if a certain combo supports 5 sprites, it supports sprite00 up to and including sprite04.
The sprites that come with the editor are all of the same size of 48 pixels tall by 48 pixel wide. If the active compatibility mode requires other sizes, entire spritesheets are scaled to match the requirements of a particular game. The size of the sprites that come with this game itself are at the correct size and don't require scaling, so there might be minor differences between the spritesets in the editor and those that come with the target game as a result of this automatic scaling in the editor. On top of this, games that support multiple zoom levels of their maps might come with a seperate set of sprite, especially made for a certain zoom level, whereas the editor always scales down from the base set of 48x48 pixel sprites.
A complete list of all sets and styles is available on this page.